These documents are quite literally self-explanatory. You can compare the raw contents of .md files here to how they appear when rendered to see what the relatively minimal set of markdown syntax results in when converted to markup.
Simply follow along with the template file which will showcase most common Markdown features and link to the other markdown files in this directory at relevant points to demonstrate the linking feature. That's honestly all you need to get up and running with Markdown, it's designed to be simple to learn and use!